const fs = require('fs')

fs.readFile('./file/01-node初识.html', 'utf-8', (err, data) => {
  if(err) throw err
  // console.log(data.toString());
  console.log(data);
})

fs.writeFile('./file/demo.txt', '\nhello itcast', err => {
  if(err) throw err
  console.log('写入成功');
})